Ref #6800 - add qpid-cpp-client-devel to comps

add qpid-cpp-client-devel to pulp fedora and rhel comps which is needed
by qpid_messaging gem. The gem allows katello to receive candlepin event
messages.
Merge pull request #4490 from dustint-rh/qpid-comps

Ref #6800 - add qpid-cpp-client-devel to comps